Windows 10: reactivating windows after reinstallation

I cannot activate windows with the same product key I previously activate it after reinstallation.

:)

 

Does Windows 7 require reactivation if...

He is using AMD already. He wants downgrading to AM3. Don't know why??

If you change HDD + RAM simultaneously, Windows 7 needs to be reactivated. Only HDD cloning shouldn't require reactivation. As you are changing mobo + HDD (prehaps RAM upgrade too), you will surely require reactivation. If you have genuine license, you should reinstall OS (you might use Windows Easy Transfer). If you don't want to reinstall, you need to uninstall HDD, interfaces/system devices, and numerous other drivers (USB, HID, Portable devices, etc.), else your OS will be unstable.
I will highly recommend to reinstall Windows 7 and enjoy your migration.

A simple trick might be like this to avoid reactivation:
1. Clone your HDD first and boot into Windows
2. Use it for at least one week
3. Replace mobo only without any other hardware change/upgrade and boot
4. Use it for at least one week
5. Do any other upgrade (RAM, Graphic card etc.)

Don't do two simultaneous downgrades/upgrades to avoid reactivation.

 

Does Windows 7 require reactivation if...

Then why does it say fs/ft i7-920 in his tag and he wants to downgrade to am3 system? to go from a am2/2+ to am3 isn't a downgrade last time I checked

 

How to reinstall and reactivate Windows 10 with an OEM license

Before you continue, I suggest you remove the bloatware by the Control Panel and uninstalling the junk. That is faster and easier, with less potential for problems, but the steps for reinstallation are as follows:

Before you do anything, backup valuable data, if any, on some form of media (i.e. USB) so you can move it onto the reinstalled Windows.

1. Download the appropriate ISO file from Microsoft and burn it to a CD or use it with a bootable USB.
   
2. (Optional if you have no internet) Download all the appropriate drivers for your machine and save them on media for later access.
   
3. Locate the product key on your machine. It is usually under the laptop on a sticker, and if not, use special software to locate it. This will be used during the reinstallation. Note that PCs sometimes auto-activate if it is in the BIOS so this step is not needed if this is case.
   
4. Boot from the bootable media (disc or USB). Continue as usual through the installation, and when the partitions screen comes up, format the current Windows partition and install in there. (The Recovery partition can be deleted, but I recommend keeping it so if anything goes wrong you can restore to factory settings). If the key doesn't work you may need to contact Microsoft and activate over phone.
   
5. After installation, install the drivers and run Windows Update and you're done.